简单实现 ios 离线地图模块

ios/AMapOffline.m

+#import <React/RCTBridgeModule.h>
+#import <MAMapKit/MAOfflineMap.h>
+
+#pragma ide diagnostic ignored "OCUnusedClassInspection"
+
+@interface AMapOffline : NSObject <RCTBridgeModule>
+@end
+
+@implementation AMapOffline
+
+RCT_EXPORT_MODULE()
+
+RCT_REMAP_METHOD(getProvinces,
+            resolveProvinces: (RCTPromiseResolveBlock) resolve
+            reject: (RCTPromiseRejectBlock) reject) {
+    NSMutableArray *provinces = [NSMutableArray new];
+    for (id item in MAOfflineMap.sharedOfflineMap.provinces) {
+        MAOfflineProvince *province = (MAOfflineProvince *) item;
+
+        NSMutableArray *cities = [NSMutableArray new];
+        for (id city in province.cities) {
+            [cities addObject:[self itemData:(MAOfflineCity *) city]];
+        }
+
+        [provinces addObject:@{
+                @"name": province.name,
+                @"size": @(province.size),
+                @"state": [self stateString:province.itemStatus],
+                @"cities": cities,
+        }];
+    }
+    for (id item in MAOfflineMap.sharedOfflineMap.municipalities) {
+        [provinces addObject:[self itemData:item]];
+    }
+    resolve(provinces);
+}
+
+RCT_REMAP_METHOD(getCities,
+            resolveCities: (RCTPromiseResolveBlock) resolve
+            reject: (RCTPromiseRejectBlock) reject) {
+    NSMutableArray *cities = [NSMutableArray new];
+    for (id city in MAOfflineMap.sharedOfflineMap.cities) {
+        [cities addObject:[self itemData:(MAOfflineCity *) city]];
+    }
+    resolve(cities);
+}
+
+RCT_EXPORT_METHOD(download:(NSString *)name) {
+    MAOfflineItem *item = [self getItem:name];
+    if (item != nil) {
+        [MAOfflineMap.sharedOfflineMap downloadItem: item
+              shouldContinueWhenAppEntersBackground:YES
+                                      downloadBlock:nil];
+    }
+}
+
+- (MAOfflineItem *)getItem:(NSString *)name {
+    BOOL (^predicate)(MAOfflineItem *, NSUInteger, BOOL *)=^BOOL (MAOfflineItem * item, NSUInteger _, BOOL *stop) {
+        return [name isEqual:item.name];
+    };
+
+    NSUInteger i = [MAOfflineMap.sharedOfflineMap.provinces indexOfObjectPassingTest:predicate];
+    if (i != NSNotFound) {
+        return MAOfflineMap.sharedOfflineMap.provinces[i];
+    }
+
+    i = [MAOfflineMap.sharedOfflineMap.municipalities indexOfObjectPassingTest:predicate];
+    if (i != NSNotFound) {
+        return MAOfflineMap.sharedOfflineMap.municipalities[i];
+    }
+
+    i = [MAOfflineMap.sharedOfflineMap.cities indexOfObjectPassingTest:predicate];
+    if (i != NSNotFound) {
+        return MAOfflineMap.sharedOfflineMap.cities[i];
+    }
+
+    return nil;
+}
+
+- (NSString *)stateString:(MAOfflineItemStatus)code {
+    NSString *state = @"";
+    if (code == MAOfflineItemStatusCached) {
+        state = @"downloading";
+    }
+    if (code == MAOfflineItemStatusExpired) {
+        state = @"expired";
+    }
+    if (code == MAOfflineItemStatusInstalled) {
+        state = @"downloaded";
+    }
+    return state;
+}
+
+- (NSDictionary *)itemData:(MAOfflineCity *)city {
+    return @{
+            @"name": city.name,
+            @"size": @(city.size),
+            @"state": [self stateString:city.itemStatus],
+    };
+}
+
+@end

src/Offline.js

@@ -4,5 +4,5 @@ const {AMapOffline} = NativeModules
 export default {
   getProvinces: () => AMapOffline.getProvinces(),
   getCities: () => AMapOffline.getCities(),
-  download: name => AMapOffline.getDownload(name),
+  download: name => AMapOffline.download(name),
 }